The present invention relates to a new crystalline aluminosilicate zeolite catalyst (hereinafter referred to ZKU-catalyst) and the method for manufacturing thereof.
Especially, the present invention relates to the new crystalline alumino-silicate zeolite catalysts (hereinafter referred to ZKU-2, ZKU-3 and ZKU-4 catalysts).
The subject of synthesizing the low molecular olefin which is the main starting material of the petrochemical industry from the C.sub.1 -compound instead of the starting material of petroleum naphtha is going into the important problem. Particularly, it is demanded for developing the catalyst suitable to synthesizing ethylene and propylene etc. from methanol.
Recently, the zeolite catalyst of synthesizing the low molecular olefin from methanol has been developed (Japanese Patent Laid-Open No. 58,499/78). Said catalyst is called the ZSM-34 catalyst. However, there is many disadvantages of being necessary to use for the conditioning agent of crystallization in relatively great amount, the nitrogen-containing organic basic compound such as coline which has the strong bad smell and the high cost and also of requiring the long periods of the crystallization of 20-25 days. The catalyst manufactured according to the prior method has the short catalytic life and the low catalytic activity and the selectivity owing to the deposition of the carbonaceous material produced during the catalytic reaction.
The present invention is the new method of so-called "seed or nucleus crystallization method".
In comparison with the prior method, so-called "seed or nucleus crystallization method" of the present invention is the new method in which the zeolite crystal itself is used for the substance of promoting the crystallization of zeolite such as the substance forming the seed or the skelton of the zeolite crystal in the process of growing the zeolite crystal.